Grinding attachment for lathes.



H. KERSHAW.

GRINDiNG ATTACHMENT FOR LATHES. APPLICATION man APR-3,1917.

13251,,94? Patented Dec. 25, 1917;

' 2 SHEETS-SHEET 1.

H. KERSHAW.

GRINDING ATTACHMENT FOR LATHE S.

APPTJCAI'IONv FILED APR. 31 1917- magma Patented 390.25, 1917..

7 2 SHEETS-SHEET 2.

UNITED STATES "PA E T OFFICE.

HARRY KERSHAW, 0F MANCHESTER. ENGLAND.

GRINDING ATTACHMENT FOR LATHES.

Specification of Letters Patent.

Patented Dec. 25, 1917.

Application filed April 2, 1917. Serial No. 159,598.

which the following is a specification.

This invention relates to internal grinding, milling, cuttlng and likemachines of the type in which the grinding wheel or cutter is carriedupon a rotary spindle which is eccentrically or radially adjustable forthe purpose of feeding the grinding wheel to the internal surface of thecylinder or other work to be machined, and to the type in which thegrinder or mill or attachment comprises a slow-moving member consistingof two parts secured together in eccentric relation to one another butmoving as one, a fast-moving member rotatably mounted on saidslow-moving member, means for varying the eccentricity of the two-partslow-moving member and means for driving said slow and. fast-movingmembers independently of one another.

The present invention consists in certain novel combinations andarrangements of parts as hereinafter described and pointed out in theappended claims.

The invention, which is hereinafter described and illustrated as appliedto the nose of a lathe mandrel, is equally applicable for use withdrilling, milling and other machine tools without any changes other thana changein the speed of rotation and the substitution of a cutter.

The invention is illustrated by the accom panying sheets of drawings, inwhich Figure 1 is a longitudinal sectional view of the grinder or millmounted on the nose of a lathe.

Fig. 2 is a section taken on line Fig. 1. v

Fig. 3 is a section taken on line y, y of Fig. l. I

Fig. 4 is a fragmentary view showing the means for effecting the fineadjustment of the cut or set, viz :the eccentricity of the mandrel. v VFig. 5 is a. view of a locking rlng herein after referred to.

Figs. 6 and 7 are detail'views of a spring cap hereinafter referred to,Fig; 7 being a w,00of

section on line 2, z of said Fig. 6, which is a side view of said cap.

1* igs. and 9 are views illustrative of an alternative form of drlveconnection between nose or back member and front or mandrel member.

Fig. 10 is'a'view showing an alternative arrangement for drivinggrinding wheel sleeve.

Fig. 11 is a diagrammatic view showing how such sleeve is driven fromcountershaft. i

Fig. 12 is a longitudinal View partly in 7 section of a modifiedarrangement of grinder or mill shown in Fig. 1; and,

Fig. 13 1s a part'plan view thereof show ing a detall hereinafterreferred to.

Like letters of reference indicate corresponding parts in the severalfigures.

Referring to the accompanying drawings, it will be observed that adesignates the face plate member, 2) the lathe spindle, 0 the base ofthe adjustable mandrel member (Z the post or mandrel of the latter, and6- Figs. 1 and 5a split locking ring, onehalf of which grips the lathespindle b,

While the, other half engages the end of the hub a of the face platemember a. This split ring member 6 locks the face plate element to thelathe spindle to prevent the entire grinder assembly from flying offduring its operation. WVith this arrangement, it will be clear that thepresent invention essentially comprises an interior slow-moving lementconsisting of the face plate member and mandrel member, and an externalfast moving element which acts as a casing for the slow-moving elementand carries the grinder wheel or equivalent element. This exteriorfast-moving casing element consists of a flanged pulley member and aflanged sleeve member which cooperate to house the eccentric connectionbetweenthe two main parts of the slow-moving member, as will hereinaftermove fully appear.

The front and rear members 0 and a are secured together in eccentricrelation to one another, as shown in Figs. 2 and 3, by means of twostuds f, f, which studs f, f are carried by the flange a of the faceplate memher a and extend through the flange 0 of the front member a.study is a master stud and serves as a pivot on which the base 0 of themandrel member can swing, while the other stud f passes through a radialslot 0 Figs. 1 and 3'in Of these studs, the

theflangec of the'said base 0, saidstuds the devic shown in Figs. 1 and3. 55;

back slow-moving member a. we when turned by a key passed through thehol or slot (7 1n the fast-moving flange g f being provided with nuts 7"which look the flanges a 0 in place after h ving been set over on a cut,said nuts being slackened 0r tightened by a box-key inserted through anaccommodation hole in the flange g of th fast-moving sleeve 9 Tocompensate for loss of weight due to'the removal of metal from theflange g in drilling the hole 9, a spring cap 71 is pushed into saidhole Fi gs. 1 and .2said cap, whichis provided, as shown in Figs. 6 and7, with'a split ring h like a piston ring and willonly move if pulled,being of the same weight as the metal removedto form the hole, retainingthe balance.

7: is a pulley loosely mounted on the hub a of, the face plate eleinentand driven from a countershaft (not shown) and at grinding wheel speed,said-pulley a having a flange i on which is mounted a roller 2' whichtakes in andreciprocates in aslot g in the flange g of the fast-movingsleeve 9 for the drive from flange 2' to flange g, or instead of aroller, a square block may be employed if desired.

In the above construction, as also in the hereinafter describedconstructions, there is provided, as and wherelrequired (but not showninthe drawings), ball bearings between the fast-moving member and theslowmoving member, especially at the end carrunning flt on thediminished end (Z of the mandrel (Z and fitting up against the shoulder(Z thereof. The bushing (Z is held in position by means of a grub screw(Z -w hich comes under the adapter 7: which car- :ries the grindingwheel 7c, and the sleeve 9 is locked on by means of the nut (Z engagingthe screwed portionof the diminished end of the mandrel (Z, keepingthe-fast-moving flanged sleeve 9 inv position.

The fine adjustment of cut orset, viz

the eccentricity of the mandrel carrying the fast-moving sleeve isellected by means of This device consists of a line threaded screw mfitted into and across the back of the slow moving flange 0, andscrewing through a block m slidably mounted in a recess m in saidslow-moving-flange c, said block at being provided with jaws M whichembrace the stud f? carried. by theflange a of the This screw shift theblockm along the recess m and byth engagement of the jaws m with thestud f which extends through the radial slot 0 in the'slow-moving flange0 causes said slow-moving flange and mandrel cl to be thrown over on thepivot 7 ever so little or the full range as required, the jawed block mengaging the stud f with clearance for the radial movement.

For the still finer adjustment of cut or set, viz :the eccentricity, ofthe mandrel carrying the fast-moving sleeve, the hole or; slot 9 for thepassageof the key-by which the .mi-

crometer screw m is turned, ismade oval for the reception see Fig. t-ofthe overshaped boss 72 of a conical andiremovable sleeve a in which isrotatably mounted the key proper vi the arrangement being such that whenthe boss a ofthesleeven isin position, the key n can be turnedwithoutthe sleevem) turning, and as-said sleeven is graduated on itssurface at n, and said key if provided in its length with an index line.or pointer a, one is enabled, given the pitch of the micrometer screw m,togefi'ect a. much finer adjustment or outer set.

In the. modified arrangementshown in Figs. lOandll, the fast-movingmember or sleeve 5/ is driven from in front of theslowmoving flanges a 0by means of a pulley 1 running on the mandrel (Z of the base 0 of theslow-moving member, saidpulley 1 en gaging the fast-moving flange 2by..n eans of studs 3 to prevent the pull of thebelt affecting thegrinding. wheel, slackening and tightening of said belt tcaused by the0rbital movement being taken up'by means of a rocking countershaft 5, asshown in lfig. 11.

- In the modified arrangenum v ,of grinder or millshown in Figs. 12 and13, the;front part g of the fast-moving sleeved. member g is madebox-shape so asto extend backward to inclose the abutting portions orflanged ends a 0 of the twopart slowmoving'member a, 0, and such boxisclosed by means of a plate P detachablyw mounted in the mouth of saidbox, asuitably disposed .slot 9 in said plate P allowing ofthepassage ofa pin 2' on the flange z" of the fastmoving -pulley 2' to drivesaidbomended.

fast-moving sleeved member gisaidpulley 2' being separable from. thebeforementioned detachable plate P.

Instead of using the accommodation hole It and spring cap hinthefrontpart g of the fast-moving member to allow of the bolts 77holding the two eccentrically disposed slow-moving members together tobe slackened or tightened, there may-be employed in lieu thereof, and asshown in Figgll3, a long peripheral slotv b formedin the wallet thebox-ended front part of the fast inoving sleeved member. 9 said slot,which is normally closed by means of a,sl ide orcshroud if, allowing ofthe insertion-of a flat spanner to slacken or tighten the bolts Further,in the Wall of the box-end of the fast-moving member there is providedthe oval hole 9* for the reception of the oval boss of the sleevecarrying key as before described with reference to Fig. 4.

Having now described my invention, What I claim as new and desire tosecure by Letters Patent of the United States is 1. A grindingattachment for lathes including in combination With the lathe spindle, aslow-moving member including a face plate having a hub fitted to saidspindle and a mandrel member having a base provided with a recess on itsinner face communicating with an arcuate slot opening at its outer face,bolts for clamping said face plate and base of the mandrel together, oneof said bolts constituting a pivot for the mandrel member and the otherof said bolts projecting through the recess and arcuate slot of saidbase, a yoke piece mounted in the recess of the base of the mandrelmember and engaging the shank of the bolt passing through the same andsaid slot for adjusting the mandrel member eccentrieally with the faceplate, a screw engaging with said yoke-piece and accessible from theperiphery of the base of the mandrel member, a fastmoving memberincluding a sleeve rotatably mounted on said mandrel member carrying atool and a pulley element.

2. A grinding attachment for lathes, including in combination with thelathe spindle, a slow-moving member consisting of a face plate having ahub to fit on the lathe spindle, a mandrel member provided with a baseeccentrieally pivoted to the face plate, a fast-moving member consistingof a flanged pulley rotatably mounted on the hub of the said face platemember, and a sleeve provided With a flange having a slot rotatablymounted on the said mandrel, said flanged pulley and flanged sleeveproviding a housing for the eccentrically connected parts of theslow-moving member, an adapter mounted on said sleeve, a grinding Wheelcarried by said adapter, a roller carried by the.

flanged pulley for engaging and reciprocating in the slot in the flangeof the fast-moving sleeve, means for varying the eccentricity of themembers of the slow-moving part, and means for clamping the slow-movingmember to the lathe spindle.

3. A grinding attachment for lathes including in combination with thelathe spindle, an interior slow-moving element consisting of a faceplate member and a mandrel member eccentrieally connected, and anexternal fast-moving element consisting of a pulley member and a sleevemember carrying a grinder Wheel, said members of the latter elementhaving portions cooperating to provide a housing for the eccentricconnection of the members of the interior element and also coupled Witheach other, and means located at the end of the mandrel member andmandrel casing member for locking the fast moving element on theslowmoving element, and means for engaging a portion of the pulleymember of the fastmoving element and the lathe spindle to lock theentire assembly to the latter.

In testimony whereof I have affixed my signature hereto, this 27 day ofFebruary, 1917.

HARRY KERSHAW.

Witnesses ERNALD S. MOSELEY, GEORGE VEAVER.

Copies of this patent may be obtained to: five cents each, by addressingthe Commissioner of Patents,

Washington, D. C.

